[http://wayland.freedesktop.org/ Wayland] is a protocol for a [[wikipedia:Compositing window manager|compositor]] to talk to its clients, as well as a library implementing this protocol. All major Linux desktop systems like Gnome, KDE do support Wayland, and there is also a reference implementation for a compositor called "Weston". [https://wayland.freedesktop.org/xserver.html XWayland] implements a compatibility layer to seamlessly run legacy X11 applications on Wayland.

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[http://wayland.freedesktop.org/ Wayland] is a protocol for a [[wikipedia:Compositing window manager|compositor]] to talk to its clients, as well as a library implementing this protocol. Many major Linux desktop environments, like Gnome and KDE, support Wayland. There is also a compositor reference implementation called "Weston". [https://wayland.freedesktop.org/xserver.html XWayland] implements a compatibility layer to seamlessly run legacy X11 applications on Wayland.

== Requirements ==

== Requirements ==

−

Wayland only works on systems using [[KMS]]. As Wayland is only a library, it is useless on its own: to replace the X Server you need a compositor such as [[#Weston]].

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Most Wayland compositors only work on systems using [[KMS]].

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Wayland by itself does not provide a graphical environment; for this you also need a compositor such as [[#Weston]] or [[Sway]], or a desktop environment that includes a compositor such as [[GNOME]] or [[KDE]].

=== Buffer API support ===

=== Buffer API support ===

−

For the GPU driver and Wayland composer to be compatible they must support the same buffer API. There are two main APIs: [[Wikipedia:Generic Buffer Management|GBM]] and [http://www.phoronix.com/scan.php?page=news_item&px=XDC2016-Device-Memory-API EGLStreams].

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For the GPU driver and Wayland compositor to be compatible they must support the same buffer API. There are two main APIs: [[Wikipedia:Generic Buffer Management|GBM]] and [http://www.phoronix.com/scan.php?page=news_item&px=XDC2016-Device-Memory-API EGLStreams].

{{Note| if X is not already configured you may need to configure a keymap: [[Keyboard configuration in Xorg]]}}

==== Screencast recording ====

==== Screencast recording ====

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=== GTK+ 3 ===

=== GTK+ 3 ===

−

The {{Pkg|gtk3}} package has the Wayland backend enabled. GTK+ will default to the X11 backend, but this can be overridden by modifying an environment variable: {{ic|GDK_BACKEND&#61;wayland}}.

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The {{Pkg|gtk3}} package has the Wayland backend enabled. GTK+ will default to the Wayland backend, but it is possible to override it to Xwayland by modifying an environment variable: {{ic|GDK_BACKEND&#61;x11}}.

=== Qt 5 ===

=== Qt 5 ===

−

The {{Grp|qt5}} package from the repositories has the Wayland support if {{Pkg|qt5-wayland}} is installed.

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To enable Wayland support in Qt 5, install the {{Pkg|qt5-wayland}} package.

−

To run a Qt 5 app with the Wayland plugin, set the {{ic|1=QT_QPA_PLATFORM=wayland-egl}} [[environment variable]]. For Arch, most QT applications do not work because of [https://bugreports.qt.io/browse/QTBUG-58423 QTBUG-58423], will be fixed with qt-5.9: https://codereview.qt-project.org/#/c/184278/ .

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To run a Qt 5 app with the Wayland plugin, use {{ic|1=-platform wayland}} or set the {{ic|1=QT_QPA_PLATFORM=wayland-egl}} [[environment variable]].

=== Clutter ===

=== Clutter ===

−

The Clutter toolkit has a Wayland backend that allows it to run as a Wayland client. The backend is enabled in the official package in extra.

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The Clutter toolkit has a Wayland backend that allows it to run as a Wayland client. The backend is enabled in the {{Pkg|clutter}} package.

To run a Clutter app on Wayland, set {{ic|CLUTTER_BACKEND&#61;wayland}}.

To run a Clutter app on Wayland, set {{ic|CLUTTER_BACKEND&#61;wayland}}.

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=== SDL2 ===

=== SDL2 ===

−

Experimental Wayland support is enabled by default on Arch Linux.

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To run a SDL2 application on Wayland, set {{ic|SDL_VIDEODRIVER&#61;wayland}}.

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=== GLFW ===

−

To run a SDL application on Wayland, set {{ic|SDL_VIDEODRIVER&#61;wayland}}.

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To use GLFW with the Wayland backend, install the {{Pkg|glfw-wayland}} package (instead of {{Pkg|glfw-x11}}).

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=== GLFW ===

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=== GLEW ===

−

Experimental wayland support is now in GLFW 3.1 and can be enabled with the {{ic|-DGLFW_USE_WAYLAND&#61;ON}} CMake option at compile time. You can also install the package {{AUR|glfw-wayland-git}} from the AUR.

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To use GLEW with the Wayland backend, install the {{Pkg|glew-wayland}} package (instead of {{Pkg|glew}}).

=== EFL ===

=== EFL ===

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To run a EFL application on Wayland, see Wayland [http://wayland.freedesktop.org/efl.html project page].

To run a EFL application on Wayland, see Wayland [http://wayland.freedesktop.org/efl.html project page].

(20161229) As of November 2016 there is an ongoing discussion how to implement screen recording. Currently the compositors implement at least basic functionality.

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Currently only {{AUR|green-recorder}} supports screen recording on Wayland (requires a GNOME session).

=== remote display ===

=== remote display ===

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=== Input grabbing in games, remote desktop and VM windows ===

=== Input grabbing in games, remote desktop and VM windows ===

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In contrast to Xorg, Wayland does not allow exclusive input device grabbing (e.g. [https://tronche.com/gui/x/xlib/input/XGrabKeyboard.html keyboard], [https://tronche.com/gui/x/xlib/input/XGrabPointer.html mouse]), instead, it depends on the Wayland compositor to pass keyboard shortcuts (extensions in development) and confine the pointer device to the application window.

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In contrast to Xorg, Wayland does not allow exclusive input device grabbing, also known as active or explicit grab (e.g. [https://tronche.com/gui/x/xlib/input/XGrabKeyboard.html keyboard], [https://tronche.com/gui/x/xlib/input/XGrabPointer.html mouse]), instead, it depends on the Wayland compositor to pass keyboard shortcuts and confine the pointer device to the application window.

This change in input grabbing breaks current applications' behavior, meaning:

This change in input grabbing breaks current applications' behavior, meaning:

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* The mouse pointer will not be restricted to the application's window which might cause a parallax effect where the location of the mouse pointer inside the window of the virtual machine or remote desktop is displaced from the host's mouse pointer.

* The mouse pointer will not be restricted to the application's window which might cause a parallax effect where the location of the mouse pointer inside the window of the virtual machine or remote desktop is displaced from the host's mouse pointer.

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Wayland protocol extensions for keyboard handling were [https://lists.freedesktop.org/archives/wayland-devel/2017-May/034130.html proposed for both] [https://lists.freedesktop.org/archives/wayland-devel/2017-May/034131.html XWayland] and [https://lists.freedesktop.org/archives/wayland-devel/2017-May/034132.html native Wayland clients], there are already extensions for handling of pointer devices ([https://cgit.freedesktop.org/wayland/wayland-protocols/tree/unstable/relative-pointer/relative-pointer-unstable-v1.xml relative pointer motion events] and [https://cgit.freedesktop.org/wayland/wayland-protocols/tree/unstable/pointer-constraints/pointer-constraints-unstable-v1.xml constraining pointer motions]) and similar support [https://lists.x.org/archives/xorg-devel/2016-September/050975.html already been added to XWayland].

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Wayland solves this by adding protocol extensions for Wayland and XWayland. Support for these extensions is needed to be added to Wayland compositors, and in the case of native Wayland clients to widget toolkits (e.g GTK, QT) and probably also to the applications themselves.

Support for these extensions need to be added to the Wayland compositor, and in the case of native Wayland clients probably also to the widget toolkit (e.g. GTK, QT) and the application itself. Currently, there are no known compositors supporting all these extensions.

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Supporting widget toolkits:

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* GTK since release 3.22.18.

== See also ==

== See also ==

Revision as of 18:39, 14 March 2018

Wayland is a protocol for a compositor to talk to its clients, as well as a library implementing this protocol. Many major Linux desktop environments, like Gnome and KDE, support Wayland. There is also a compositor reference implementation called "Weston". XWayland implements a compatibility layer to seamlessly run legacy X11 applications on Wayland.

Screencast recording

Weston has build-in screencast recording which can be started and stopped by pressing the Super+r key combination. Screencasts are saved to the file capture.wcap in the current working directory of Weston.

The WCAP format is a lossless video format specific to Weston, which only records the difference in frames. To be able to play the recorded screencast, the WCAP file will need to be converted to a format which a media player can understand. First, convert the capture to the YUV pixel format:

Velox is a simple window manager based on swc. It is inspired by dwm and xmonad.

Orbital

Stacking

Orbital is a Wayland compositor and shell, using Qt5 and Weston. The goal of the project is to build a simple yet flexible and good looking Wayland desktop. It is not a full fledged DE but rather the analogue of a WM in the X11 world, such as Awesome or Fluxbox.

Liri Shell

Stacking

Liri Shell is the desktop shell for Liri, built using QtQuick and QtCompositor as a compositor for Wayland.

Maynard

(Unclear)

Maynard is a desktop shell client for Weston based on GTK. It was based on weston-gtk-shell, a project by Tiago Vignatti.

Motorcar

(Unclear)

Motorcar is a Wayland compositor to explore 3D windowing using virtual reality.

Way Cooler

Tiling

way-coolerAUR is a customizable (Lua config files) Wayland compositor written in Rust. Inspired by i3 and awesome.

Grefsen is a Qt/Wayland compositor providing a minimal desktop environment.

Some of installed wayland desktop clients might store information in /usr/share/wayland-sessions/*.desktop files about how to start them in wayland.

Troubleshooting

Running graphical applications as root

Trying to run a graphical application as root via su, sudo or pkexec in a Wayland session (e.g.GParted or Gedit), be it in a terminal emulator or from a graphical component, will fail with an error similar to this:

Before Wayland, running GUI applications with elevated privileges could be properly implemented by creating a Polkit policy, or more dangerously done by running the command in a terminal by prepending the command with sudo; but under (X)Wayland this does not work anymore as the default has been made to only allow the user who started the X server to connect clients to it (see the bug report and theupstreamcommits it refers to).

The most straightforward workaround is to use xhost to temporarily allow the root user to access the local user's X session. To do so, execute the following command as the current (unprivileged) user[1]:

xhost si:localuser:root

To remove this access after the application has been closed:

xhost -si:localuser:root

Note: This GNOME bug report suggests two other workarounds, with one specific to editing text files.

This article or section needs language, wiki syntax or style improvements. See Help:Style for reference.

Reason: Many of these subsections should go into a "Known issues" section (i.e., there is no solution currently). Additionally prepending a date is not needed. (Discuss in Talk:Wayland#)

LLVM assertion failure

If you get an LLVM assertion failure, you need to rebuild mesa without Gallium LLVM until this problem is fixed.

This may imply disabling some drivers which require LLVM.
You may also try exporting the following, if having problems with hardware drivers:

$ export EGL_DRIVER=/usr/lib/egl/egl_gallium.so

Slow motion, graphical glitches, and crashes

Gnome-shell users may experience display issues when they switch to Wayland from X. One of the root cause might be the CLUTTER_PAINT=disable-clipped-redraws:disable-culling set by yourself for Xorg-based gnome-shell. Just try to remove it from /etc/environment or other rc files to see if everything goes back to normal.

weston-terminal

liteide

screen recording

Currently only green-recorderAUR supports screen recording on Wayland (requires a GNOME session).

remote display

(20161229) there was a merge of FreeRDP into weston in 2013, enabled via compile time switch. The arch linux weston package currently has it not enabled.

Input grabbing in games, remote desktop and VM windows

In contrast to Xorg, Wayland does not allow exclusive input device grabbing, also known as active or explicit grab (e.g. keyboard, mouse), instead, it depends on the Wayland compositor to pass keyboard shortcuts and confine the pointer device to the application window.

This change in input grabbing breaks current applications' behavior, meaning:

Hotkey combinations and modifiers will be caught by the compositor and won't be sent to remote desktop and virtual machine windows.

The mouse pointer will not be restricted to the application's window which might cause a parallax effect where the location of the mouse pointer inside the window of the virtual machine or remote desktop is displaced from the host's mouse pointer.

Wayland solves this by adding protocol extensions for Wayland and XWayland. Support for these extensions is needed to be added to Wayland compositors, and in the case of native Wayland clients to widget toolkits (e.g GTK, QT) and probably also to the applications themselves.